Fresh install of mate, Firefox has GUI issues. The dialogue boxes are empty and really small. The Options menu is unusable. Attached are screenshots.
This does not appear to be linked to the theme, as changing it to other default themes did not solve the issue.
The terminal did not display any errors or warnings.
I have tried it on all other installations and it works fine. I also briefly tried it on Manjaro MATE and it works fine, so I do not think this is an upstream issue. Oddly Firefox is the only application that is apparently having this trouble. I tried other menus and all appear to be relatively fine.
I had to do a fresh install with another DE for the time being as I mostly use Firefox on my PC and as of now it is unusable. This issue was present in the old 17.7 and the current 17.8 ISOs.